Arrival At Carcasses
Kaija Gahm
2022-10-10
Analyzing arrival order at carcasses
IDENTIFY FEEDING EVENTS
Let’s move on to examining an individual’s movement patterns to identify arrival at a carcass site. Going to pick the individual with the longest run:
Acceleration
Visualize acceleration
Okay, that’s not very informative, as expected. Let’s split this by day
and just look at one day’s sequence.
Okay, this is kind of cool. But I’m not good enough at interpreting
accelerometer data to know for sure how to read this.
Speed and altitude
What about speed and altitude? Can the combination of those tell us
what we need to know?
Relative altitude
In order for this to make any sense at all, we need to
cross-reference these measurements with elevation data for Israel. We
can obtain this using the elevatr package.
Speed/relative altitude plots
Now let’s re-do the speed and altitude plots, using altitude above
ground:
KNOWN FEEDING EVENTS
Feeding event data
Read in the feeding event data (this is the most updated version we have; should work on getting more info from more recent feeding events.)
Sunrise/sunset, day/night to datAnnot
## [1] 75## feeding_date feeding_time death_of_carcass_known hours_since_death
## 1 8/30/2020 11:30:00 AM no 24
## 2 9/1/2020 2:15:00 PM no 24
## 3 9/4/2020 10:55:00 AM no 24
## 4 9/6/2020 11:10:00 AM no 24
## 5 9/7/2020 9:20:00 AM no 24
## 6 9/10/2020 1:00:00 PM no 12
## area feeding_station carcass_type weight_of_food
## 1 SdeBoker_Hatira Tzaror_trap donkey, sheep, horse 350
## 2 Small_and_Big_crater Small_crater_view ibex, sheep 130
## 3 SdeBoker_Hatira Tzaror_trap sheep, calf 310
## 4 South_Judean_desert Ben_Yair_view sheep, cow 660
## 5 SdeBoker_Hatira Antenas cow 600
## 6 Ramon_crater Kaolin calf, cow 540
## no_of_carcasses origin_carcass ranger remarks
## 1 3 בדואים עין עבדת לטובת לכידת נשרים
## 2 3 הר הנגב עודד צעירי הונח גם עוף מסוג אמו
## 3 7 מקרר עין עבדת לטובת לכידות נשרים
## 4 2 טללי שדה ג'מיל אל אטרש
## 5 1 טללי שדה יבגני קמינסקי
## 6 2 קיבוץ צאלים ידידה שמואל הצבת שוקת מים
## datetime
## 1 2020-08-30 10:56:53
## 2 2020-09-01 13:16:41
## 3 2020-09-04 09:55:39
## 4 2020-09-06 10:13:52
## 5 2020-09-07 08:40:28
## 6 2020-09-10 12:26:09##
## Arava_valley Ramon_crater SdeBoker_Hatira
## 7 11 28
## Small_and_Big_crater South_Judean_desert West_negev_sands
## 22 6 1Feeding station locations
Okay, now that we have that data, we critically need access to the feeding station data so that we can match these carcass drops to lat/long.
## Feeding_station Active_Not_active ITM_E ITM_N lat long
## 1 Antenas yes 178602 538292 30.9349 34.7770
## 2 Gorni_hill yes 228080 580867 31.319568 35.2951
## 3 Golhan yes 203938 533826 30.8952 35.0422
## 4 Daroch yes 184290 530148 30.8616 34.8368
## 5 Camus_south yes 205225 540429 30.9548 35.0556
## 6 Hahalak_mount yes 203447 530437 30.8646 35.0371## [1] TRUE TRUE TRUE TRUE TRUE TRUE TRUE TRUE TRUE TRUE TRUE TRUE TRUE TRUE TRUE
## [16] TRUE TRUE TRUE TRUE TRUE TRUE TRUE TRUE TRUE TRUE TRUE TRUE TRUE TRUE TRUE
## [31] TRUE TRUE TRUE TRUE TRUE TRUE TRUE TRUE TRUE TRUE TRUE TRUE TRUE TRUE TRUE
## [46] TRUE TRUE TRUE TRUE TRUE TRUE TRUE TRUE TRUE TRUE TRUE TRUE TRUE TRUE TRUE
## [61] TRUE TRUE TRUE TRUE TRUE TRUE TRUE TRUE TRUE TRUE TRUE TRUE TRUE TRUE TRUE## Warning in mask$eval_all_mutate(quo): NAs introduced by coercion
## Warning in mask$eval_all_mutate(quo): NAs introduced by coercion## feeding_date feeding_time death_of_carcass_known hours_since_death
## 1 8/30/2020 11:30:00 AM no 24
## 2 9/1/2020 2:15:00 PM no 24
## 3 9/4/2020 10:55:00 AM no 24
## 4 9/6/2020 11:10:00 AM no 24
## 5 9/7/2020 9:20:00 AM no 24
## 6 9/10/2020 1:00:00 PM no 12
## area feeding_station carcass_type weight_of_food
## 1 SdeBoker_Hatira Tzaror_trap donkey, sheep, horse 350
## 2 Small_and_Big_crater Small_crater_view ibex, sheep 130
## 3 SdeBoker_Hatira Tzaror_trap sheep, calf 310
## 4 South_Judean_desert Ben_Yair_view sheep, cow 660
## 5 SdeBoker_Hatira Antenas cow 600
## 6 Ramon_crater Kaolin calf, cow 540
## no_of_carcasses origin_carcass ranger remarks
## 1 3 בדואים עין עבדת לטובת לכידת נשרים
## 2 3 הר הנגב עודד צעירי הונח גם עוף מסוג אמו
## 3 7 מקרר עין עבדת לטובת לכידות נשרים
## 4 2 טללי שדה ג'מיל אל אטרש
## 5 1 טללי שדה יבגני קמינסקי
## 6 2 קיבוץ צאלים ידידה שמואל הצבת שוקת מים
## datetime lat long
## 1 2020-08-30 10:56:53 30.8615 34.8136
## 2 2020-09-01 13:16:41 30.9490 35.1508
## 3 2020-09-04 09:55:39 30.8615 34.8136
## 4 2020-09-06 10:13:52 31.3321 35.3305
## 5 2020-09-07 08:40:28 30.9349 34.7770
## 6 2020-09-10 12:26:09 NA 34.8491Exploratory mapping
## Reading layer `CutOffRegion.kml' from data source
## `/Users/kaijagahmpersonalprojects/Desktop/dataExploration/data/CutOffRegion.kml'
## using driver `KML'
## Simple feature collection with 1 feature and 2 fields
## Geometry type: POLYGON
## Dimension: XYZ
## Bounding box: xmin: 33.46685 ymin: 29.47732 xmax: 36.72913 ymax: 33.51767
## z_range: zmin: 0 zmax: 0
## Geodetic CRS: WGS 84## 428x252 terrain-background map image from Stamen Maps.
## See ?ggmap to plot it.
Okay, now that I know how to plot points and I know when and where the feeding events have occurred, time to plot points around each feeding station, color-coded by individual, around the time of the feeding events.
## Simple feature collection with 6 features and 10 fields
## Geometry type: POINT
## Dimension: XY
## Bounding box: xmin: 34.777 ymin: 30.8615 xmax: 35.3305 ymax: 31.3321
## Geodetic CRS: WGS 84
## feeding_date feeding_time area feeding_station
## 1 8/30/2020 11:30:00 AM SdeBoker_Hatira Tzaror_trap
## 2 9/1/2020 2:15:00 PM Small_and_Big_crater Small_crater_view
## 3 9/4/2020 10:55:00 AM SdeBoker_Hatira Tzaror_trap
## 4 9/6/2020 11:10:00 AM South_Judean_desert Ben_Yair_view
## 5 9/7/2020 9:20:00 AM SdeBoker_Hatira Antenas
## 6 9/12/2020 10:00:00 AM SdeBoker_Hatira Tzaror_trap
## carcass_type weight_of_food no_of_carcasses datetime
## 1 donkey, sheep, horse 350 3 2020-08-30 10:56:53
## 2 ibex, sheep 130 3 2020-09-01 13:16:41
## 3 sheep, calf 310 7 2020-09-04 09:55:39
## 4 sheep, cow 660 2 2020-09-06 10:13:52
## 5 cow 600 1 2020-09-07 08:40:28
## 6 sheep, calf 300 6 2020-09-12 09:00:47
## lat long geometry
## 1 30.8615 34.8136 POINT (34.8136 30.8615)
## 2 30.9490 35.1508 POINT (35.1508 30.949)
## 3 30.8615 34.8136 POINT (34.8136 30.8615)
## 4 31.3321 35.3305 POINT (35.3305 31.3321)
## 5 30.9349 34.7770 POINT (34.777 30.9349)
## 6 30.8615 34.8136 POINT (34.8136 30.8615)
Distance from carcass vs. time
In the supplementary material of Harel et al. 2016, it says that carcasses are usually discovered and consumed within “a few days,” and that feeding by other scavengers also contributes to this. To be conservative, I’m going to examine a 4-day period after carcass deposition, regardless of when the vultures find the carcass. So that’s 96 hours.
I was going to try to animate this, but instead I’m just going to calculate distance over time and plot it. Duh.
Do this for all feeding events.
